Introduction: The purpose of this study was assessment of the ability of techniques of Cine-phase contrast MRI using rapid spiral acquisition to measure normal human renal blood flow in vivo. Fifteen normal volunteers were studies with Cine-phase contrast MRI. Methods: A breathheld technique employing rapid spiral acquisition [Spiral-PC], and a Cine-PC technique which allowed resolution of both cardiac and respiratory cycles employing rapid spiral acquisition [SPR-PC] were employed. Total arterial renal blood flow was calculated for each individual. Measurements of renal blood flow via standard techniques of PAH clearance-hematrocrit were obtained for each subject the same day as the MRI examinations. Results: The agreement between normal renal blood flow measurements for the PAH clearance techniques and the various Cine-PC techniques employing spiral acquisition was very good, with the SPR-PC technique giving the best agreement, when data in end expiration was analyzed. A two standard deviation range of agreement between this latter technique with the PAH clearance-hematocrit value was 115%. Conclusions: The Cine-PC techniques employing rapid spiral acquisitions appear capable of accurate in vivo measurement of human renal blood flow. The techniques give a good deal of promise for clinical measurement of renal blood flow which may be reduced in such conditions as renal artery stenosis.